feat(ui-lvgl): quick panel from the status bar; L2 fixes from rc1

The quick panel, as a phone's: pulled down from the status bar (or a tap
on it). Bluetooth, WiFi, GPS, sound, trail and live share switch at a
tap; Advert opens the advert popup (moved here from the Nodes header);
Lock locks the screen; a brightness slider. Holding a tile opens its
settings. Lock and sun glyphs added to the fonts.

Fixes from rc1 testing on the L2:
- GPS status icon: none when GPS is off (the module kept its last fix
  valid, so it stayed green); grey on, green with a fix. ensureGps()
  turns GPS on before trusting that stale fix.
- Screen wake: the panel wakes dark, a frame is drawn, then the
  backlight fades in -- no white flash. Off fades out first.
- Power off / flat battery: the chip wakes every 30 s to look for USB
  power and starts when plugged in (it slept with no wake source before,
  until the reset button). Plugged in when switched off: stays off until
  re-plugged.
- Message ages in a conversation refresh every 2 s, as on ui-new; the
  message popup keeps its age, repeaters heard and delivery up to date.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

variants/wio-tracker-l2/WioTrackerL2Board.h

@@ -82,6 +82,9 @@ public:
   // VBUS presence via the AW35615 USB-C controller (I2C 0x22)
   bool isExternalPowered() override;
 
+  // Off (Power off, or the battery ran down): see the .cpp
+  void powerOff() override;
+
 private:
   uint8_t out_shadow[2] = { 0xFF, 0xFF };  // TCA9535 output regs default high
   uint8_t cfg_shadow[2] = { 0xFF, 0xFF };  // 1 = input (power-on default)